...one clarification to my post above, the HD600 was selected as I understand it is relatively neutral (so that I have a point of reference), while the T90 and HE-400 were selected for having a slightly fun sound signature, with T90 overall balance slightly toward the upper end, and the HE-400 overall balance in the lower end of the frequencies.

First, thanks to all the contributors to this thread. I am just jumping into the headphone game (but have been a long time audio enthusiast with a pretty good speaker setup). After reading every post I could find I decided to purchase 3 headphones at the same time, then listen to all of them over a month or so, keep the one I like and then sell the other two.

Since I get my audiophile sound fix (i.e. neutral) from my speaker setup, I think I may be more interested in a slightly fun sound signature from my headphones to mix it up.

Therefore, I bought the HD600, HE-400 and the T90. The HD600 and HE-400 have now been through the burn-in process and the T-90's will have about 100 hours burn-in on them after today, then the 3-way shoot out begins.

Just based upon early listening sessions, I am currently leaning toward keeping the T90 or HE-400, but we shall see.

We couldn't be much more similar with our headphone inventory :-)! Having tried all three, I just sold my HD650 yesterday. Waiting for my Philips X1 to arrive today, but so far T90 is my most fav of them all....

We couldn't be much more similar with our headphone inventory :-)! Having tried all three, I just sold my HD650 yesterday. Waiting for my Philips X1 to arrive today, but so far T90 is my most fav of them all....

the problem I have with his review,is that it seems to me he just opened the box,started listening and evaluating. bad form. you can see his opinions changing over time,..plus,iirc,his now moved on to "bigger and better things" so I don't know how much time transpired. the one thing of value that I did pick up from him is that the T90 seems to scale better,which makes sense to me considering the nature of beyer's tesla tech and specs.

something that isn't mentioned much here. when discussing the tesla tech,most just mention that it's about efficiency in regards to amplification. I think it's much more than that.

...because the magnetic field is so powerful and can exert so much control over the diaphragm,they are also able to make the diaphragm material thinner and lighter. this means that it's able to stop and move much quicker than normal and that contributes to it's sonic performance.

on the whole,i would say the beyer tesla driver is much more sophisticated than the HD700(specifically) driver but the senn housing is much more sophisticated with probably much more R&D and T&E. however,neither one of those can tell you which you would prefer sonically.

just a thought.

also,looking at the FR graph. the T90 at 20HZ is only about 3 dB and at 30Hz 2 dB from the upper bass. that's very impressive for a dynamic driver and very similar to the linear bass that planar magnetics can achieve all the way to the lows.

just a note. I received the t90s about a week ago. I can only say that their sound signature has changed radically over the first 100 hours of usage and burn in. Burn in may be a figment of the imagination or user adaptation but i gotta say that this phone went from unbearably bright to the best phone i own so far>including grado r1, akg 701s and hd 600s which is my favorite phone up till now.

the problem I have with his review,is that it seems to me he just opened the box,started listening and evaluating. bad form. you can see his opinions changing over time,..plus,iirc,his now moved on to "bigger and better things" so I don't know how much time transpired. the one thing of value that I did pick up from him is that the T90 seems to scale better,which makes sense to me considering the nature of beyer's tesla tech and specs.

Just sold my T90 this week. It had about 150 hours burn in. I was using it daily at work at one point. Definitely a brain burn in headphone. I listened to it right before I sold it and coming from HD800 and HE-500, the T90 was very bright even through Crack. Another characteristic of the T90 is a smaller than average soundstage compared to open back headphones. This is not necessarily bad, as it can give a more intimate sound good for rock music. I tried it with Quickie in chain and it helped immensely on the soundstaging. Still it had a bright and sibilant sound I remember hearing at beginning but going away with burn in, but now I see it was mostly brain burn in. EQing like others have said will help until you're used to it.

The HD700 I sold a while back but I remember it to have an overall agreeable signature. The biggest flaw I remember is that it was noticeably grainy and lacked the refinement when A/Bing with T90 and HE-500. Even the KEF M500 doesn't seem to have this problem, though I never A/Bed it with the HD700. I think this is due to the drop in the upper mids at 2-3kHz. Just compare the graphs of the headphones I own/owned: HD700, T90, HE-500, and HD800. Only the HD700 has this drop and to me only it has this problem. I also have the UE900 and it has the same problem of graininess and lacking of refinement, and people have attributed this to the well known drop in the upper mids of the UE900. Ultimately, this is probably subjective if you find it grainy, and likely depends on what other headphones you're used to. Besides that, the HD700 has one of the better sound signatures I've heard. The T90? Well maybe after some brain burn in. Definitely not an agreeable signature without EQing or right of the bat.Edited by Sonido - 1/24/14 at 3:45pm